Lifting-jack.



M. K. PURDY.

'LIFTINGJACK.

APPLICATION FILED JUNE 30, I915;

'1, 170,992. Patented Feb. 8, 1916.

MARTIN K. PURDY, 0F EASTON,

. SPENCE, OF EASTON, PENNSYLVANIA.

.LIFTING-JACK. j

Specification ofiLettei's Patent.

Patented Feb. 8, 1916.

Application filed June 30, 1915. Serial No. 37,266.

To all whom it may concern:

Be it known that I, MARTIN K. PURDY, a citizen of the United States, residing at Easton, in the county of Northampton and State of Pennsylvania, have invented cer-' tain new and useful Improvements in Lifting-Jacks; and I do hereby declare the following to be a full, clear, and exact descrip- This invention relates to new and useful improvements in collapsible or telescoping liftmg jacks and conslsts of a simple and efficient devlce of this nature havlng varlous details of construction, combinations and arrangements of parts which will be hereinafter fully described, shown in the accompanying drawings and then specifically defined in the appended claim.

My invention is illustrated in the accompanying drawings, in which:

Figure 1 is a side elevation of the jack. Fig. 2 is a view in elevation of the apparatus, parts being broken away. Fig. 3 is an enlarged detail view of the ratchet mechanism for rotating the screw.

Reference now being had to the details of the drawings by letter, A designates the base of the lifting jack having a hollow upright standard B with oppositely disposed slots 0 therein, one marginal edge of each slot being provided with notches D adapted to receive the projecting ends of the pins F which pass diametrically through the shell E which telescopes within the standard B and adapted to hold said shell at diflerent elevations. The upper end of the shell E is provided with a flange E having a raceway in the upper surface thereof for the reception of the ball bearings F, and H designates a ratchet wheel having an interior opening, threaded to engage the screw 1, which latter is provided with a swiveled top I. The under surface of said set screw has a semispherical bearing F for the reception of the ball bearing F which also engages a raceway formed in the upper surface of the flange E. A yoke L engages over said flange and ratchet wheel and holds the same in contact with the ball bearings, and pivotally mounted on a projecting arm of said yoke is a handle N with forked ends N which receives pivotal pin 0, passing through an opening R formed in a projecting lug S of said yoke, said armsbeing adapted to engage the teeth of the ratchet wheel for the purpose of imparting a rotary I Said movement thereto and to the screw. handle, when not in use, is adapted to swing upon its pivot so that the forked arms thereof will be out of engagement with the teeth of the ratchet wheel.

The operation of my. invention will be readily understood and is as follows :The shell which telescopes within the standard B may be held at different elevations by causing the pin Fto engage one or another-of, the notches D, after which, by swinging the lever to a horizontal position so that the forked arms at the ends thereof will engage the teeth ofthe ratchet wheel, the latter may PENNSYLVANIA, ,ASSIGNOR or ONEJ-IJALE rro JOHN H.

be rotated in one direction or the other, 7

causing the screw to rotate and be raised or lowered, accordingly as the ratchet wheel is moved in one direction or the other. When not in use, the parts may be reduced to a compact form and the handle made to assume a position parallel with the standard.

By the provision of a lifting jack made in accordance with my invention, it will be noted that a simple and efficient device is afforded, occupying a small space, when not 7 in use, and which may be readily adjusted for use in the manner shown and described.

What I claim to be new is A lifting jack comprising a hollow supporting base, a shell telescoping therein and designed to be held at different elevations and terminating in a flange at its upper end with a raceway at its upper surface, a screw movable within said shell, a ratchet wheel with a threaded opening engaging the threads of the screw, ball bearings interposed between the wheel and flange, a yoke having a downwardly projecting portion with a slot with walls tapering outward from its central portion, the lower end of said projection having an angled part extending underneath the flange, an oppositely disposed projection of the yoke being bent In testimony whereof I hereunto affix my at rlght angles and extending also undersignature in presence of two Witnesses.

neath said flange, a handle hzWina forked ,7

end, a pin engaging the arms of iihe forked MARTIN PURDL 5 end and having a rocking movement in said Witnesses:

slots, the end of the arms designed to engage GEO. ALsovER,

the teeth of the ratchet Wheel. EDITH PURDY.

Gupiea of this patent may be obtained for five cents each, by addressing the Commissioner of Eatents,

- Washington, D. 0. 

